Method and apparatus for concentrating and evaporating sugar sirups



1930. a. R. BAKER ET AL. ,744,096

METHOD AND APPARATUS FOR CONCENTRATING AND EVAPORATING SUGAR SIRUPS= Filed Dec. 21. 1926 lvll l lullbllol lolllfi o c n c a O GEORGE. RALPH BAKER, WILLIAM EDWARD PREsoom'.

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Patented Jan. 21, 1930 UNITED STATES PATENT. OFFICE GEORGE RALPH BAKER AND WILLIAM EDWARD PRESCOTT, OF WILLESDEN JUN CTION, LONDON, ENGLAND, ASSIGNORS TO BAKER PERKINS COMPANY INCORPORATED, OF NEW YORK, N. Y., A-CORPORATION OF NEW YORK METHOD AND AP PABATUS FOR CONCENTRATING AND EVAPORATING SUGAR SIRUPS I Application filed December 21, 1926, Serial No.

This invention relates to methods and apparatus for concentrating and evaporating sugar sirups and the like, and involves a contained in a jacket surrounding the outer tube,

but the present invention comprises meansfor heating the sirup to be treated by means of gas, which does not require a separate power producing plant or equivalent as in the case of steam referredto. i

The'invention includes means for obtaining a uniform transfer of heat to the sirup under treatment in all parts of the evaporating area.

In order to obtain a uniform transfer of heat the heating elements are suitablv located close to the outer tube so that the flames .play on to the surface of the tube. The heating elements are appropriately arranged around the tube and said elements are evenly spaced in order to impart uniform heating over the entire evaporating surface. V

In the use of gas burners these are preferably of the pre-mixiug variety, that is to say, gas and air in the correct proportions for complete combustion are fed to the burners. To ensure a perfectly even distribution of heat over the inner surface of the evaporating wall or tube, such wall may be made of substantial thickness so that the heat applied to its outer surface may penetrate evenly through the mass of the metal due to its conductivity. The whole apparatus may be enclosed by an outer casing or tube having suitable means for carrying ofi' products of combustion. and at or adjacent the outlet for the concentrated or evaporated sirup there may be provided thermostatic means by which the heating elements may be controlled accord- .ing to a predetermined required temperature so that an even distribution of heat maybe 156,162, and in Great Britain January 1, 1926.

obtained throughout the apparatus. The said thermostatic means may be adjustable accordingto the degree of heat to be imparted to the sirup under treatment. Such control would however usually be adopted in addition to appropriate manual controlling means for the heating elements.

An embodiment of the improved apparatus to which the heat is applied by means of gas burners is illustrated in the accompanying drawings in which Fig. 1 is a partsectional front elevation, Fig. 2 a part-sectional side elevation, Fig. 3 is a cross-section on line 33 of Fig. 1 and Fig. 4: a cross-section on line 4i of Fig. 2.

The concentrating and evaporating vessel comprises outer and inner tubes.;a and b, respectively; between which is the passage for the sirup constituted by the spiral plate 0, the said passage being of gradually increasing area from top to bottom. The sirup is fed to the top at a by any convenient means between the tubes a and b and is discharged at the lower end through a nozzle 6 aboutwhich is located a gas burner ring 6 Any other convenient form of evaporating vessel embodying the spiral passage feature may however be adopted.

The said concentrating and evaporating vessel may be supported by a' bracket or arm (Z as hereafter explained, and surrounding the upper and lower end portions of said vessel both above and below are castings or heads 6 e each provided with an annular gas channel e and formed in two halves or segments bolted together as indicated in Fig. 4. Extending towards the center from each of said castin s or heads 6 e is a series of as i es communicating with the annular channel e in the respective head, these gas pipes being arranged closely around the exterior of the outer tube a of the concentrating vessel in a circle and being provided with burner noz-' zles or nipples f suitably disposed at different angles tangential to the surface of the tube so that the flames emitted play evenly or uniformly over the whole of such surface.

The aforesaid castings or heads are supplied with gas or air by means of pipes 9 shown as provided at each side of the conpinging thereon from the burners f and that the heat furnished may be uniform throughoutor may be varied as to the upper and lower parts of the concentrating vessel by controlling the supply of gas to the respective heads As previously mentioned, thermostatic means may be provided by which the supply of gas may be controlled according to a predetermined required temperature, and such device is more particularly shown in Figs. and 4 where it is designated i. In this device the operation is due to the diflerence of expansion between two members, for example the bracket or arm d and the outer tube a of the concentrating vessel. The said tube a has connected thereto, as by brazing, a spider i (Fig. 3 secured within the bracket and having a ange i (Fig. 2) which rests on the,

bracket d and thus supports theconcentrating vessel. A cap (I? is fitted around part of the spider and is secured by bolts (1 At the lower end the tube a may be centered by means of a similar spider i The tube a is also provided with a flange j to which is Y riveted or otherwise attached one end of a bar j the other end of which is adjustably connected as by a screw and nut to the rod j of the valve (not shown) of the thermostat. Thus when the tube a expands, due to the heat communicated to it, the bar 7' will cause the rod 7' of the thermostat to be drawn down but the bracket will remain comparatively cool, and the aforesaid valve in the thermostat i will be closed, which in turn will close through connection I the diaphragm valve l of the governor l, thus shutting oif supply of gas through the governor by way of pipe k to the burners, the overnor being fed through pipe 1?. By ;ad ustment of the screw and nut j the supply of gas can be controlled through the thermostat for heating the concentrating element to a .predetermined temperature. In Fig. 2, I: designates a pipe by which any surplus or leakage of gas from the thermostat may be. delivered adjacent one of the burners f and there burnt.

What we claim as our invention and desire to secure by Letters Patent of the United States is 1. In apparatus for concentrating and evaporating sugar sirups, the combination of a concentrating vessel'containing a spiral pas- 1,744,oee

sage for the sirup, and vertical gas pipes surrounding the outer surface. of said vessel and provided with burner nipples disposed tangentially to the surface of the concentrating vessel at different angles so as to cause the flames emitted to play uniformly over the surface of said vessel.

2. Apparatus for concentrating and evaporating sugar sirups, comprising a concentrating vessel; upper and lower annular heads encircling the top and bottom portions of the vessel; an annular series of gas pipes extending from each head toward the central portion of the vessel and disposed to surround said vessel in close proximit to its outer surface, said pipes being provi ed with a plurality of burner nipples directed immediately toward said surface; a pair of gas supply pipes extending vertically in opposite directions and attached at their outer ends to said heads, the lower ends of said supply pipes being located opposite the said central portion of said vessel; a main source of gas; and a separate connection between such source and each sup- P y p p 3. Concentrating apparatus, according to claim 1, in which the gas pipes surrounding the concentrating-vessel are divided into separate upper and lower series, each series having controlling means for regulating the supply of gas thereto independently of the otherseries. f

4. A method of concentrating and evaporating sugar sirups, comprising 'the ste s of passing the sirup continuously throug an elongated chamber, and constantly directing flames at close range tangentially against the external wall of the chamber on all sides thereof in a manner to play uniformly over the surface of such wall.

5. A method of concentrating and evaporating sugar sirups, comprising the steps of passing the sirup continuously through an elongated chamber, andconstantly directing flames at different angles against the external wall of the chamber on all sides thereof in a manner to play uniformly over the surface of such wall.

6. A method of concentrating and evaporating sugar sirups, comprising the steps of passing the sirup continuously throughan elongated chamber, and constantly directing flames at close range tangentially against the external wall of the chamber on all sides thereof in a manner to play uniformly over the surface of such wall, while automatically regulating the action of the flames throughout the heating oper tion according to a predetermined require temperature.

In witness whereof we have signed this specification.

GEORGE RALPH BAKER. WILLIAM EDWARD PRESCOTT. 

